From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752668AbaIAWNy (ORCPT ); Mon, 1 Sep 2014 18:13:54 -0400 Received: from mga02.intel.com ([134.134.136.20]:42172 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752031AbaIAWNx (ORCPT ); Mon, 1 Sep 2014 18:13:53 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,445,1406617200"; d="scan'208";a="566789979" Date: Mon, 1 Sep 2014 23:13:44 +0100 From: Damien Lespiau To: Alan Stern Cc: Daniel Vetter , intel-gfx , Kernel development list Subject: Re: [Intel-gfx] Regression in drm-intel caused by d91a2cb8e510 Message-ID: <20140901221344.GA22902@strange.ger.corp.intel.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 01, 2014 at 04:19:23PM -0400, Alan Stern wrote: > Daniel: > > I'm encountering a problem with the drm-intel-nightly branch in your > drm-intel repository. The symptom is that when I boot my laptop, at > some point during the start-up procedure the screen goes totally blank, > as though the backlight were turned off, and it remains that way. I > can't tell if the backlight really is off -- it may be that there's > just nothing being displayed -- and playing with the screen-brightness > function keys doesn't help. > > Git bisect located the source of the problem as commit d91a2cb8e510 > (drm/i915: Add 180 degree primary plane rotation support). The problem > occurs when I boot a kernel built from that commit, and it doesn't > occur when I boot a kernel built from the preceding commit > (19ac737dc3c3). > > If necessary, I can get debugging info by logging in over a network > connection. Tell me what you need. It seems like Ville and Mika already caught a similar bug today, could you give Ville's patch a go (available on the intel-gfx): drm/i915: Don't call intel_plane_restore() when the prop value didn't change Thanks, -- Damien